A jar contains $4$ red balls, $3$ green balls, and $7$ blue balls. If a ball is randomly chosen, what is the probability that it is not blue?
There are $4 + 3 + 7 = 14$ balls in the jar. There are $7$ blue balls. That means $14 - 7 = 7$ are not blue. The probability is $ \frac{7}{14} = \dfrac{1}{2}$.